1. Field of the Invention
At least one embodiment of the invention relates to a unipolar multipurpose electrode line.
2. Description of the Related Art
Implantable defibrillators or cardioverters (ICD) have been known for quite some time and used for clinical applications, and for decades they have been the subject of continuous technical enhancements. This applies to an even greater extent to implantable cardiac pacemakers and the related electrode lines. Combined cardiac stimulation and defibrillation assemblies, including the electrode lines (ICD electrodes) specially developed therefore, have also become established in the device market and in clinical practice as a special device category. Such combination devices are referred to as cardiac pacemakers for cardiac resynchronization therapy with defibrillators, in short CRT-D devices.
FIG. 1 shows a schematic illustration of such an assembly 100 comprising electrodes to be run into the heart H of a patient. A cardiac stimulation and defibrillation device 110 is thus connected to the heart H by way of an electrode line 120, which comprises three legs or electrode feed lines 130, 140 and 150. At or near the distal end, all legs carry sensing or stimulation electrodes (which are not individually denoted), and the leg 150 additionally carries an elongated defibrillation electrode 160. In the assembly shown, the leg 130 runs in the right atrium and the leg 140 runs in the left ventricle of the heart H, and the leg 150 carrying the defibrillation electrode 160 runs in the right ventricle (RV).
The presently available ICD electrode lines comprise a plurality of feed wires that are insulated from each other and a plurality of or multipolar plug contacts between the electrode line and the pulse generator. This makes these electrode lines expensive to produce and prone to defects. Moreover, the connection blocks of the pulse generators are large and expensive, and it is possible for users to connect the electrodes in a faulty manner. In addition, the required high voltage insulation distances within the electrode line necessitate a minimum diameter of the electrodes. Consequently installation space for shielding measures for producing MRI-compatible ICD electrodes is lost, or options of low-voltage electrodes cannot be applied to high-voltage electrodes.